Manure and fertilizer emissions linked
Comparing Manure applied to Soils — Emissions (N2O) with Synthetic Fertilizers — Direct emissions (N2O) across 155 countries, 2023–2050.
- Rank correlation
- +0.84
- Holding size constant
- +0.53
- Countries compared
- 155
- Period
- 2023–2050
What might link these
The relationship between manure and synthetic fertilizer emissions might be driven by agricultural practices, with countries using more fertilizers also having more livestock, leading to increased manure emissions. A careful reader should consider the potential role of agricultural land area as a confounder. The correlation suggests a connection, but its meaning requires further exploration.
Why this is not proof of anything
This is a correlation across countries, not an experiment. It cannot show that either indicator causes the other, and both may simply follow a third thing. This correlation could mislead by implying a direct relationship between the two types of emissions, when in fact they might be driven by underlying factors like agricultural land use or crop selection.
The second figure above repeats the measurement with national population and income held constant. It is the more conservative number: a relationship that largely disappears there was mostly telling you that larger, richer countries have more of most things.
How this was measured
Both indicators were ranked across every country reporting each, and the two rankings compared — ranks rather than raw values, because a handful of very large countries can otherwise manufacture a relationship on their own. The calculation is arithmetic over figures already published on this site; the commentary above is drafted from the two indicator names and the resulting coefficients.